Modern scuba diving gear consists of one or more gas tanks strapped to the divers back, connected to an air hose and an invention called the demand regulator. The demand regulator controls the flow of air, so that the air pressure within the diver’s lungs equals the pressure of the water.
Early Diving Gear
Ancient swimmers used cut hollow reeds to breathe air, the first rudimentary snorkel used to enhance our abilities underwater. Around 1300, Persian divers were making rudimentary eye goggles from the thinly sliced and polished shells of tortoises. By the 16th century, wooden barrels were used as primitive diving bells, and for the first time divers could travel underwater with more than one breath of air, but not much more than one.
More Than One Breath
In 1771, British engineer, John Smeaton invented the air pump. A hose was connected between the air pump and the diving barrel, allowing air to be pumped to the diver. In 1772, Frenchmen, Sieur Freminet invented a rebreathing device that recycled the exhaled air from inside of the barrel, this was the first self-contained air device. Freminet’s invention was a poor one, the inventor died from lack of oxygen after being in his own device for twenty minutes.
In 1825, English inventor, William James designed another self-contained breather, a cylindrical iron “belt” attached to a copper helmet. The belt held about 450 psi of air, enough for a seven-minute dive.
In 1876, Englishmen, Henry Fleuss invented a closed circuit, oxygen rebreather. His invention was originally intended to be used in the repair of an iron door of a flooded ship’s chamber. Fleuss then decided to use his invention for a thirty-foot deep dive underwater. He died from the pure oxygen; oxygen is toxic to humans under pressure.
Rigid Diving Suits
In 1873, Benoît Rouquayrol and Auguste Denayrouze built a new piece of equipment a rigid diving suit with a safer air supply, however it weighed about 200 pounds.

Houdini Suit – 1921
Famous magician and escape artist, Harry Houdini (born Ehrich Weiss in Budapest, Hungary in 1874) was also an inventor. Harry Houdini astonished audiences by escaping from handcuffs, straitjackets, and locked boxes, often doing so underwater. Houdini’s invention for a diver’s suit permitted divers, in case of danger, to quickly divest themselves of the suit while submerged and to safely escape and reach the surface of the water.
Jacques Cousteau & Emile Gagnan
Emile Gagnan and Jacques Cousteau invented the modern demand regulator and an improved autonomous diving suit. In 1942, redesigned a car regulator and invented a demand regulator that would automatically fresh air when a diver breathed. A year later in 1943, Cousteau and Gagnan began selling the Aqua-Lung which was the  first commercially successful scuba ,  open-circuit units  in which compressed gas (usually air) is inhaled from a tank and then exhaled into the water adjacent to the tank. However, the scuba regulators of today trace their origins to Australia, where Ted Eldred developed the first mouth piece regulator, known as the Porpoise. This regulator was developed because patents protected the Aqualung’s double hose design. It separated the cylinder from the demand valve giving the diver air at the same pressure surrounding his mouth, not surrounding the tank.

The open circuit systems were developed after Cousteau had a number of incidents of oxygen toxicity using a rebreather system, in which exhaled air is reprocessed to remove carbon dioxide. Modern versions of rebreather systems (both semi-closed circuit and closed circuit) are still available today, and form the second main type of scuba unit, most commonly used for technical diving, such as deep diving.
How can we breathe underwater?
Water normally contains the dissolved oxygen from which fish and other aquatic animals extract all their required oxygen as the water flows past their gills. Humans lack gills and do not otherwise have the capacity to breathe underwater unaided by external devices. Although the feasibility of filling and artificially ventilating the lungs with a dedicated liquid (liquid breathing) has been established for some time, the size and complexity of the equipment allows only for medical applications with current technology.
Early diving experimenters quickly discovered it is not enough simply to supply air to breathe comfortably underwater. As one descends, in addition to the normal atmospheric pressure, water exerts increasing pressure on the chest and lungs—approximately 1 bar (14.7 pounds per square inch) for every 33 feet (10 m) of depth—so the pressure of the inhaled breath must almost exactly counter the surrounding or ambient pressure to inflate the lungs. It generally becomes difficult to breathe through a tube past three feet under the water.
By always providing the breathing gas at ambient pressure, modern demand valve regulators ensure the diver can inhale and exhale naturally and virtually effortlessly, regardless of depth.
Because the diver’s nose and eyes are covered by a diving mask; the diver cannot breathe in through the nose, except when wearing a full face diving mask. However, inhaling from a regulator’s mouthpiece becomes second nature very quickly.
Here at DJL, we are proud to be using new Aqualung Calypso regulators. These have the following features:
- High flow, in line piston first stage, meaning it is simple and reliable.
- Extremely cost efficient to maintain.
- Compact first stage, very lightweight second stage.
- VAS (Venturi adjustment switch) to prevent free flows at the surface and provide maximum airflow at depth.
When you are ready to purchase your own gear, pop into the shop for a chat and we will be able to get you the best set to suit your needs!
Article compiled with the kind assistance of Wikipedia and About.com